1.6.1 Outline the data required to solve a problem that the students have not encountered before, including data file formats, input and output requirements with appropriate user interfaces. For example, screens, OMR forms, report formats.
Design concepts The design concepts provide the software designer with a foundation from which more sophisticated methods can be applied. A set of fundamental design concepts has evolved. They are:
Abstraction - Abstraction is the process or result of generalization by reducing the information content of a concept or an observable phenomenon, typically in order to retain only information which is relevant for a particular purpose.
Refinement - It is the process of elaboration. A hierarchy is developed by decomposing a macroscopic statement of function in a stepwise fashion until programming language statements are reached. In each step, one or several instructions of a given program are decomposed into more detailed instructions. Abstraction and Refinement are complementary concepts.
Modularity - Software architecture is divided into components called modules.
Software Architecture - It refers to the overall structure of the software and the ways in which that structure provides conceptual integrity for a system. A good software architecture will yield a good return on investment with respect to the desired outcome of the project, e.g. in terms of performance, quality, schedule and cost.
Control Hierarchy - A program structure that represent the organization of a program components and implies a hierarchy of control.
Structural Partitioning - The program structure can be divided both horizontally and vertically. Horizontal partitions define separate branches of modular hierarchy for each major program function. Vertical partitioning suggests that control and work should be distributed top down in the program structure.
Data Structure - It is a representation of the logical relationship among individual elements of data.
Software Procedure - It focuses on the processing of each modules individually
Information Hiding - Modules should be specified and designed so that information contained within a module is inaccessible to other modules that have no need for such information.
Design considerations
There are many aspects to consider in the design of a piece of software. The importance of each should reflect the goals the software is trying to achieve. Some of these aspects are:
Compatibility - The software is able to operate with other products that are designed for interoperability with another product. For example, a piece of software may be backward-compatible with an older version of itself.
Extensibility - New capabilities can be added to the software without major changes to the underlying architecture.
Fault-tolerance - The software is resistant to and able to recover from component failure.
Maintainability - The software can be restored to a specified condition within
a specified period of time. For example, antivirus software may include the ability to periodically receive virus definition updates in order to maintain the software's effectiveness.
Modularity - the resulting software comprises well defined, independent components. That leads to better maintainability. The components could be then implemented and tested in isolation before being integrated to form a desired software system. This allows division of work in a software development project.
Packaging - Printed material such as the box and manuals should match the style designated for the target market and should enhance usability. All compatibility information should be visible on the outside of the package. All components required for use should be included in the package or specified as a requirement on the outside of the package.
Reliability - The software is able to perform a required function under stated conditions for a specified period of time.
Reusability - the software is able to add further features and modification with slight or no modification.
Robustness - The software is able to operate under stress or tolerate unpredictable or invalid input. For example, it can be designed with a resilience to low memory conditions.
Security - The software is able to withstand hostile acts and influences.
Usability - The software user interface must be usable for its target user/audience. Default values for the parameters must be chosen so that they are a good choice for the majority of the users.
Modeling language
A modeling language is any artificial language that can be used to express information or knowle
dge or systems in a structure that is defined by a consistent set of rules. The rules are used for interpretation of the meaning of components in the structure. A modeling language can be graphical or textual. Examples of graphical modelling languages for software design are:
Business Process Modeling Notation (BPMN) is an example of a Process Modeling language.
EXPRESS and EXPRESS-G (ISO 10303-11) is an international standard general-purpose data modeling language.
Extended Enterprise Modeling Language (EEML) is commonly used for business process modeling across a number of layers.
Flowchart is a schematic representation of an algorithm or a stepwise process,
Fundamental Modeling Concepts (FMC) modeling language for software-intensive systems.
IDEF is a family of modeling languages, the most notable of which include IDEF0 for functional modeling, IDEF1X for information modeling, and IDEF5 for modeling ontologies.
Jackson Structured Programming (JSP) is a method for structured programming based on correspondences between data stream structure and program structure
LePUS3 is an object-oriented visual Design Description Language and a formal specification language that is suitable primarily for modelling large object-oriented (Java, C++, C#) programs and design patterns.
Unified Modeling Language (UML) is a general modeling language to describe software both structurally and behaviorally. It has a graphical notation and allows for extension with a Profile (UML).
Alloy (specification language) is a general purpose specification language for expressing complex structural constraints and behavior in a software system. It provides a concise language based on first-order relational logic.
Systems Modeling Language (SysML) is a new general-purpose modeling language for systems engineering.
1.6.2 Discuss the advantages of modularity in designing a solution to problems.
The term 'Module' refers to a small component of a larger system that can
operate within that system independently from the operations of the other components. Modularity is the property of computer programs that measures the extent to which they have been composed out of separate parts called modules. A modular approach to programming is gaining popularity in fields of artificial intelligence systems integration, where a large-scale general A.I. system is composed of modules that each serve a specific purpose and communicate with each other to produce the system's overall behavior. Programs that have many direct interrelationships between any two random parts of the program code are less modular than programs where those relationships occur mainly at well-defined interfaces between modules.
1.6.3 Define the term prototyping.
Prototyping is the process of quickly putting together a working model (a prototype) in order to test various aspects of a design, illustrate ideas or features and gather early user feedback. Prototyping is often treated as an integral part of the system design process, where it is believed to reduce project risk and cost. Often one or more prototypes are made in a process of incremental development where each prototype is influenced by the performance of previous designs, in this way problems or deficiencies in design can be corrected. When the prototype is sufficiently refined and meets the functionality, robustness, manufacturability and other design goals, the product is ready for production.
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1.6.1 Outline the data required to solve a problem that the students have not encountered before, including data file formats, input and output requirements with appropriate user interfaces. For example, screens, OMR forms, report formats.
Design concepts
The design concepts provide the software designer with a foundation from which more sophisticated methods can be applied. A set of fundamental design concepts has evolved. They are:
Design considerations
There are many aspects to consider in the design of a piece of software. The importance of each should reflect the goals the software is trying to achieve. Some of these aspects are:
a specified period of time. For example, antivirus software may include the ability to periodically receive virus definition updates in order to maintain the software's effectiveness.
Modeling language
A modeling language is any artificial language that can be used to express information or knowle
dge or systems in a structure that is defined by a consistent set of rules. The rules are used for interpretation of the meaning of components in the structure. A modeling language can be graphical or textual. Examples of graphical modelling languages for software design are:1.6.2 Discuss the advantages of modularity in designing a solution to problems.
The term 'Module' refers to a small component of a larger system that can
operate within that system independently from the operations of the other components. Modularity is the property of computer programs that measures the extent to which they have been composed out of separate parts called modules. A modular approach to programming is gaining popularity in fields of artificial intelligence systems integration, where a large-scale general A.I. system is composed of modules that each serve a specific purpose and communicate with each other to produce the system's overall behavior. Programs that have many direct interrelationships between any two random parts of the program code are less modular than programs where those relationships occur mainly at well-defined interfaces between modules.1.6.3 Define the term prototyping.
Prototyping is the process of quickly putting together a working model (a prototype) in order to test various aspects of a design, illustrate ideas or features and gather early user feedback. Prototyping is often treated as an integral part of the system design process, where it is believed to reduce project risk and cost. Often one or more prototypes are made in a process of incremental development where each prototype is influenced by the performance of previous designs, in this way problems or deficiencies in design can be corrected. When the prototype is sufficiently refined and meets the functionality, robustness, manufacturability and other design goals, the product is ready for production.Best content in StJulians_ComputerScience | Diigo - Groups